Apparatus for forming blanks of ceramic material.



' B. A. JEFFERY.

APPARATUS FOR FORMING BLANKS OF CERAMIC MATERIAL.

APPLICATION FILED APR. I9, I9I3.

WTNESSES /NI/ENTOR B. A. JEFFERY.

- APPARATUS FOR FOH'MING BLANKS 0F CERAMIC MATERIAL.

APPLICATION FILED APH.19.1913.

IN VEN TOI? A Ilm/125g Patented May 22, 1917.

2 SHEETSASHEET '2.

BENJAMIN A. JEFFERY, 0F DETROIT, MICI-IICrAIN'.-

APPARATUS FOR FORMING BLANKS OF CERAMIC MATERIAL.

Specification of Letters Patent. y

Patented May 22, ioiv.

Application led April 19, 1913. Serial No.` 762,440.

To all whom t may concern:

Be it known that I, BENJAMIN A. JEFFERY, a citizen of the United States, residing at Detroit, in the county of I/Vayne and' Staten of l/fichigan, have invented new and useful Improvements in Apparatus for Forming Blanks of Ceramic Material, of which the following,- is a specification.

This invention relates to certain new and useful improvements in apparatus for forming blanks of ceramic material.

In the manufacture of porcelain `insulating plugs for ignition devices, as well as other similar articles made of porcelain, it is common practice to place a mass of the plastic clay upon a rapidly revolving table, the material being roughly shaped by hand. to the desired form so as to provide blanks, said blanks being allowedto stand a predetermined period, i. e., until they reach. the condition known as green" `or half hard. This preliminary shaping is known as throwing The blank while in the greenjgV .state is brought to the nished shape by being placed upon a turning lathe, the sired contour being imparted by means steel tools held in the hand of the operator,A` or otherwise positioned over the clay. After turning, the blank is dipped into a suitable glaze and then placed in the kiln and fired. In practice it is found that after the blank is formed by ythrowing itmust be very carefully handled to preventcollapse and distortion while being placed upon drying trays, and in such handling as may be necessary before the same is in condition for turning. It will be understood, of course, that the clay is very soft and plastic and the slightest touch by unskilled hands destroys the blank. It is obvious therefore that' a high degree of skill is necessary to form the blank by throwing and to handle it in the subsequent operations. One of the objects of the present invention is to provide an improved apparatus by means of which the blank may be more uniformly shaped than is possible with thrown work, 'and the material rendered more uniform 'and compact. A further Objectis to provide an apparatus by means of which the blanks may be more rapidly formed than by throwing. A further object is to provide means for handling the blanks after they have been formed and. 'while still. in a plastic condr tion so that they will be protected from collapse and distortion.

The invention will be hereinafter fully set forth and particularly pointed out in the claims.

In vthe accompanying drawing Figure 1 is a side elevation of an expressing machine and its actuating mechanism. Fig. 2 is a detail perspective view illustrating the cover and its adjuncts. Fig. 3 is a longitudinal sectional view of Fig. 2. Fig. 4; is a detail view illustrating a wire core adapted to `coperate with said expressing machine.

Referring to the drawings, 10 designates a supporting frame in which is mounted a driving shaft 11 and a driven shaft 12, the driving shaft receiving power from any suitable source through .a pulley 13. The shaft is moved longitudinally by means of the bell crank lever 14 adjustably connected with a treadle 15, a suitable clutch 16 serving to connect the shafts 11 and 12. Shaft 12 is Iprovided with a worm meshing with a. worm lgear 16 having a threaded engagement with a vertical shaft 17 to the upper end of which is connected .a piston 18 adapted to traverse the length of the receiving chamber 19. Said chamber is provided with a removable cover 20 which is held in position by suitable locking rods 21. The cover 2O is preferablyl of conical form and provided with a reduced die-like opening 22. Centrally located in said Opening is a core-pin 23 which is supported by a suitable spider secured to the top 20 at a point wellbelow the die-opening 22, the upper end of said core-pin being recessed as indicated at 24. Extendinglupwardly from the top of the cover 2O is a rod 25 to which is adjustably secured a gage 26 having a V-shaped recess 27 in' one end, the converging walls of said recessfterminating in a circular portion 28 in perpendicular alinement with the core pin 23.

\ Coperating with the gage 26 and the core pin 23-is a co-re rod 30 having a reduced end 31` arranged to enter the seat 24.A of the core pin 23, the other end of said rod being loosely seated in the recess 28 of the gage 26. Secured to the rod in .any suitable manner is a circular disk 32, said disk being provided with an opening through which the rod 30 is passed. It will be ob served that said disk is located contiguous to one end of the rod. Pivotally mounted on the top of cover is a lever 33 provided with a cutting wire 34, said lever being so mounted as to permit the wire 34 to swing transversely across the opening 22 above the upper end of the core pin 23.

In practice, a suitable plastic clay is placed within the receiving chamber 19, after which the cover 20 is secured in position. The gage 26 is then kadjusted to the proper position after which a core rod 30 is placed with its reduced end resting in the seat 24, the upper end resting in the recess 28 and projecting above the gage 26. rlhe disk 32 passes under the Agage 26 and is spaced therefrom a short distance. When the operator presses downwardly on the treadle 15 the shafts 11 and 12 are connected through the clutch 16, and the piston 18 operates to force the plastic clay upwardly through the die-opening 22. As the clay passes through said opening the core pin 23 forms a longitudinal bore therein, the mass being delivered in perfect cylindrical form. As the discharged. mass rises is passes over the core rod 30, embedding the latter in the cylindrical body. The expressed material continues to rise as long as the treadle 15 is depressed, and when the upper end of the blank thus formed engages the disk 32 the latter is moved upwardly, elevating the rod 30 so as to disengage the latter from the pin 23. When the disk 32 comes in contact with the gage 26 the pressure is taken 0E the treadle 15 arresting the movement of the piston 18, and the lever 33 is swung so that the wire 34 will sever the blank close to the top of the die-opening. The operator may then grasp the protruding upper end of the rod 30 and remove the blank which may be placed upon a tray or other suitable support and allowed to rest until the clay has hardened sufficiently to retain its shape after which the core rod 30 may be removed in any suitable manner. Just as soon as the blank has been removed a new core rod 30 is placed in position and the operation repeated until the desired number of blanks have been completed.

It is sometimes desirable to manufacture cylindrical blanks without the central bore, and it is obvious that such blanks may be produced by my improved apparatus by omitting the core-wire 23 and dispensing with the core rod 30 and its adjuncts, ,movement of the piston 18 being arrested when the top of the blank contacts with the gage 26. y

From what has been said it will be'seen that by means ofmy improved apparatus the blanks are of more uniform structure than when thrown, and may be made much more rapidly and without employing skilled labor. By providing the core-rod 30 and embedding the same within the blank while the latter is still plastic, the shape of the blank is retained and the blank may be handled with greater facility and without danger of injury.

Having thus explained the nature of my invention and described an operative man? 'receiving the plastic material and provided with a die opening, means for forcing said plastic material through the die opening, and means for supporting a removable core member in a stationary position outside of said chamber and in alinement with the center of said die opening, whereby the outcoming plastic material is forced over the core member. y i l '2.-An apparatus for forming blanks of ceramic material comprising a chamber for receiving the plastic material and provided with a die opening, means for forcing said plastic material through the die opening, and means for supporting a removable core member in a stationary position outside of said chamber and in alinement with the center of said die opening, whereby the outcoming plastic material is forced over the core member, and a gage supported opposite said die opening and having a seat for said core member.

3. An apparatus for forming blanks of ceramic material comprising a chamber for receiving the plastic material and provided with a die-opening, means for forcingsaid material through said opening, means for forming a bore in the expressed material, a gage having a stop portion in alinement with said die-opening, and a removable coremember supported in alinement with said bore forming means.

4. An apparatus for forming blanks of ceramic material comprising a chamber for receiving the plastic material and provided with a die-opening, a core pin located in said die-opening and provided with a recess, means for forcing the material through said opening, and a removable core member having one end adapted to seat in said recess.

5. An apparatus for forming blanks of ceramic material comprising a chamber for receiving the plastic material and provided with a die-opening, a core pin located in said opening, a gage having a stop portion ceramic material comprising a chamber for receiving the plastic material and provided With a die-opening, a core pin located in said opening,- a stop having a portion in alinement with said opening, means for forcing the material through said opening, and a removable core member having one end adapted to rest upon said core pin, said stop being provided with a recess to receive the other end of said core member.

7. An apparatus for forming blanks of ceramic material comprising a chamber for receiving the plastic material and provided With a die-opening, a core pin located in said opening and having its exposed end recessed to form a seat, a gage having an adjustable stop portion in alinement With said dieopening, and a removable core member having one end adapted to rest in said seat, said stop being provided with a recess to receive the other end of said core-member.

8. In an apparatus for forming blanks of ceramic material, a chamber for receiving the plastic material and provided With a dieopening, a gage having a stop portion in alinement with said opening, and means for forcing said material through said opening in combination with a removable core member having an abutment adapted to contact with said stop.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

BENJAMIN A. JEFFERY.

Witnesses:

MoRrIi/mn C. DEWETT, R. W. GREEN.

Copies of this patent mav be obtained for ve cents each, by addressing' the "Commissioner of Patents. Washington, D. C. 

